External battery



FIG. 1 is a perspective view of a external battery showing my new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a left side elevational view thereof;

FIG. 5 is a right side elevational view thereof;

FIG. 6 is a top plan view thereof; and,

FIG. 7 is a bottom plan view thereof.

The broken lines / dotted lines / are intended to show features that are environmental only and form no part of the claimed design. 

The ornamental design for an external battery, as shown and described. 